1. Field of the Invention
This invention relates to cardboard boxes and especially to rectangular-shaped containers having a top or side opening for dispensing the contents thereof.
In particular, the container closure of this invention is adapted for sealing containing apertures or spouts.
2. Description of the Prior Art
Consumer products are frequently marketed in cardboard or paperboard boxes and usually have a rectilinear configuration. These containers are conveniently stackable on store shelves and are readily storable within the consumer's cupboard. Frequently, the containers are also provided with apertures or spouts for dispensing the contents directly therefrom.
These types of dispensing boxes are typically found in connection with food products such as cereals, rice, sugar, pasta, raisins, etc. They are also widely used for cleaning preparations such as powdered soap and detergents.
The box construction generally employs an access opening having interfitting closure flaps formed as an integral portion of the box top, a break-away lift tab at a corner of the box top, or a tab and slot arrangement along the upper surface of the box. Some containers have a pouring spout incorporated in a sidewall of the container adjacent the top. It should also be apparent that containers are available in various dimensions dependent in part, upon the nature of the contents and the net weight.
A problem encountered with the aforementioned dispensing containers was that they were inefficient for providing an airtight seal. This was a distinct disadvantage with food products, since they were subject to spoilage and thus the contents would become stale or rancid. Furthermore, improperly sealed food packages were susceptible to roach or insect infestation or other contamination. With regard to nonedible contents such as cleaning preparations, moisture could chemically react and adversely affect the contents, or there would be loss due to spillage.
An attempt to prolong the shelf life of open food containers included the use of refoldable innerbags. This device, however, was not particularly successful for the reason that the innerbags were frequently torn when initially opened or after repeated usage. Furthermore, this system required the careful refolding of the bag after each dispensing of the contents. Another method for preserving freshness of food contents was by the use of BHT* and other antioxidants in the packaging material; however, the use of these substances were objectionable to many consumers. FNT *Butylated Hydroxytoluene
Alternate solutions for providing an auxiliary container cover was shown in U.S. Pat. No. 4,249,693. The device of that patent, however, did not provide a structure for closely conforming to the walls of the container and thus did not provide an effective seal. Another disadvantage was that the cover did not have any positive securement to the container and thus could accidently become dislodged.
Another shortcoming of the previous box closures such as shown in U.S. Pat. Nos. 3,265,282, 3,695,504, and 3,733,022 was that those devices were not adaptable for use with a range of different container widths.
The device of the instant invention in contrast, is adjustably adapted for grippingly engaging different size containers to provide a tight seal.